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Volatility/X · Analytics Library

Volatility estimation built for your application

Volatility/X is a high-performance ActiveX/COM software library that delivers the best available methods for computing implied and statistical volatility — directly inside Excel, Visual Basic, C++, or any COM-compatible environment. The single most critical input to any pricing model, now accessible from your application or a spreadsheet cell.

Volatility estimation done right

Volatility/X provides a comprehensive suite of implied and statistical volatility estimators as an ActiveX/COM software library with a full Excel Add-In — compute volatility directly in your application or spreadsheet.

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Implied Volatility

Reverse-engineer market expectations from option prices using high-precision numerical solvers. Build volatility surfaces and identify relative value across the strike spectrum.

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Statistical Volatility

Multiple estimators for historical volatility — from simple close-to-close through advanced range-based methods. Choose the right estimator for your data and market conditions.

Volatility Skew

Analyse how implied volatility varies across strikes. Detect skew changes that signal shifts in market sentiment and risk pricing.

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Excel Add-In

Includes a full Excel Add-In with context-sensitive help. Access every volatility function directly from any cell — just like native Excel formulas.

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Pairs with Options/X

Designed to work seamlessly with Options/X and other Windale products. Feed accurate volatility estimates directly into your pricing models via COM integration.

Multi-Asset Coverage

Estimate volatility for equities, indices, commodities, and FX. One component for every asset class your desk monitors.

Comprehensive implied and statistical methods

Volatility/X includes 14 estimation methods across implied volatility, historical volatility, and volatility conversion — the most comprehensive toolkit available as an ActiveX/COM software library.

Implied Volatility

Exact Bisection — Black-Scholes

Robust bracketing solver for call and put implied volatility using the Black-Scholes model. Guaranteed convergence.

Exact Bisection — Binomial

Implied volatility extraction using the binomial pricing model for call and put options, including American-style contracts.

M. Li (2006)

Analytical approximation for call option implied volatility with rapid convergence and high accuracy.

Brenner & Subrahmanyam (1988)

Closed-form approximation for call and put implied volatility. Also available with Vega-refined iterative improvement.

Bharadia (1996)

Efficient analytical approximation for call and put implied volatility with minimal computational overhead.

Corrado & Miller (1996)

Widely-cited closed-form approximation for call and put implied volatility, accurate across a broad range of moneyness.

Hallerbach (2004)

Refined analytical approximation for call and put implied volatility with improved accuracy near the money.

Historical / Statistical Volatility

Classical Historical Volatility

Standard deviation of log returns — the baseline close-to-close estimator used across the industry.

Parkinson (1980)

Range-based estimator using high-low prices. Up to 5x more efficient than close-to-close.

Garman & Klass (1980)

Extends Parkinson with open and close prices. Up to 8x more efficient than close-to-close.

Rogers & Satchell (1991)

Incorporates drift (non-zero mean returns), providing more accurate estimates for trending markets.

EWMA

Exponentially Weighted Moving Average — gives greater weight to recent observations, ideal for capturing volatility regime changes.

Volatility Conversion

Time Period & Scale Conversion

Convert volatility estimates between different time periods and scales — daily to annual, weekly to monthly, and any custom interval.

Impact of Volatility Estimation Error on Option Prices
$0.50 $0.40 $0.30 $0.20 $0.10 Call — 30d, OTM $0.28 $0.37 +30% error Put — 180d, OTM $0.28 $0.43 +56% error Correct volatility (10%) 20% overestimate (12%)

Small errors in volatility give big errors in option prices

Every option pricing model takes volatility as an input. A 20% overestimation of the returns variance can lead to a 30% mispricing of an out-of-the-money call — and a 56% error on a longer-dated put. If your volatility estimate is inaccurate, every price, every Greek, and every risk number downstream is wrong.

Volatility/X implements the most efficient estimation algorithms available — Garman-Klass achieves 7.4× the efficiency of classical estimators, requiring far less data to achieve the same accuracy. Compare multiple estimators side by side, understand how they diverge under different market conditions, and select the method that best fits your asset class and trading horizon.

14
Estimation methods
7.4×
Efficiency gain
0
Dependencies

Try Volatility/X free

Full-featured trial with all 14 estimation methods and direct access to Dr. Back for technical questions.